063.Python前端Django分页器
Django的分页器
1 前期准备
创建一个数据库,用于存放数据
mysql> create database pager default charset=utf8;
mysql> use pager;
setting注册
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'pager',
'HOST': '127.0.0.1',
'PORT': 3306,
'USER': 'root',
'PASSWORD': '123456',
}
}
配置__init__
import pymysql
pymysql.install_as_MySQLdb()
模型数据models.py
from django.db import models # Create your models here.
class Book(models.Model):
title = models.CharField(max_length=32)
price = models.DecimalField(max_digits=5,decimal_places=2)
执行数据迁移操作
root@darren-virtual-machine:~/PycharmProjects/cbv_test# python3 manage.py makemigrations
root@darren-virtual-machine:~/PycharmProjects/cbv_test# python3 manage.py migrate
数据库
mysql> desc app01_book;
配置路由
from django.urls import path,re_path
from app01 import views urlpatterns = [
path('login_fbv/',views.login),
path('login_cbv/', views.Login.as_view()),
path('book_list/',views.Booklist.as_view()),
]
views文件
#分页器
from app01.models import Book
#from app01 import models
import random
class Booklist(View):
def get(self,request):
for i in range(1,101):
Book.objects.create(title="book_%s" % i,price = random.randint(30,200))
Book.objects.create
return render(request,"book_list.html")
book_list.html
#分页器
from app01.models import Book
#from app01 import models
import random
class Booklist(View):
def get(self,request):
for i in range(1,101):
Book.objects.create(title="book_%s" % i,price = random.randint(30,200))
Book.objects.create
return render(request,"book_list.html")
访问http://127.0.0.1:8000/app01/book_list/
查看数据库
mysql> select * from app01_book;
这种方式比较慢
方法二:
mysql> delete from app01_book;
#分页器
from app01.models import Book
#from app01 import models
import random
class Booklist(View):
def get(self,request):
temp_list = []
for i in range(1,101):
#Book.objects.create(title="book_%s" % i,price = random.randint(30,200))
temp_list.append(Book(title="book_%s" % i,price = random.randint(30,200)))
Book.objects.bulk_create(temp_list)
return render(request,"book_list.html")
访问http://127.0.0.1:8000/app01/book_list/
mysql> select * from app01_book;
+-----+----------+--------+
| id | title | price |
+-----+----------+--------+
| 101 | book_1 | 195.00 |
| 102 | book_2 | 95.00 |
| 103 | book_3 | 69.00 |
| 104 | book_4 | 118.00 |
| 105 | book_5 | 108.00 |
| 106 | book_6 | 165.00 |
....略...
| 199 | book_99 | 34.00 |
| 200 | book_100 | 99.00 |
+-----+----------+--------+
已经插入数据,速度比较快,同时及时注释掉创建数据的内容
显示书名和价格
#分页器
from app01.models import Book
#from app01 import models
import random
class Booklist(View):
def get(self,request):
#temp_list = []
#for i in range(1,101):
#Book.objects.create(title="book_%s" % i,price = random.randint(30,200))
# temp_list.append(Book(title="book_%s" % i,price = random.randint(30,200)))
#Book.objects.bulk_create(temp_list)
book_list = Book.objects.all()
#把book_list传到模板层
return render(request,"book_list.html",{
"book_list":book_list,
})
book_list.html文件
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<h3>图书列表</h3>
<ul>
{% for book in book_list %}
<li>{{ book.title }}---价格---{{ book.price }}</li>
{% endfor %}
</ul>
</body>
</html>
访问http://127.0.0.1:8000/app01/book_list/
已经显示到页面上,导入分页器
2 分页器语法
#分页器
from app01.models import Book
#from app01 import models
import random
from django.core.paginator import Paginator
class Booklist(View):
def get(self,request):
#temp_list = []
#for i in range(1,101):
#Book.objects.create(title="book_%s" % i,price = random.randint(30,200))
# temp_list.append(Book(title="book_%s" % i,price = random.randint(30,200)))
#Book.objects.bulk_create(temp_list)
book_list = Book.objects.all()
#分页器的基本语法
# 实例化分页器对象
paginator = Paginator(book_list, 10)
print("count", paginator.count) # 数据的总数
print("num_pages", paginator.num_pages) # 分页的总页数
print("page_range", paginator.page_range) # 页数的范围列表 #把book_list传到模板层
return render(request,"book_list.html",{
"book_list":book_list,
})
访问http://127.0.0.1:8000/app01/book_list/,调试输出
count 100 #100条数据
num_pages 10 #10页
page_range range(1, 11) #1-11
[10/Apr/2020 14:36:42] "GET /app01/book_list/ HTTP/1.1" 200 4906
显示每一页数据
#分页器
from app01.models import Book
#from app01 import models
import random
from django.core.paginator import Paginator
class Booklist(View):
def get(self,request):
#temp_list = []
#for i in range(1,101):
#Book.objects.create(title="book_%s" % i,price = random.randint(30,200))
# temp_list.append(Book(title="book_%s" % i,price = random.randint(30,200)))
#Book.objects.bulk_create(temp_list)
book_list = Book.objects.all()
#分页器的基本语法
# 实例化分页器对象
paginator = Paginator(book_list, 10)
#print("count", paginator.count) # 数据的总数
#print("num_pages", paginator.num_pages) # 分页的总页数
#print("page_range", paginator.page_range) # 页数的范围列表
page1 = paginator.get_page(1)
for i in page1:
print(i)
#把book_list传到模板层
return render(request,"book_list.html",{
"book_list":book_list,
})
访问http://127.0.0.1:8000/app01/book_list/,调试输出
Book object (101)
Book object (102)
Book object (103)
Book object (104)
Book object (105)
Book object (106)
Book object (107)
Book object (108)
Book object (109)
Book object (110)
获取对象
#分页器
from app01.models import Book
#from app01 import models
import random
from django.core.paginator import Paginator
class Booklist(View):
def get(self,request):
#temp_list = []
#for i in range(1,101):
#Book.objects.create(title="book_%s" % i,price = random.randint(30,200))
# temp_list.append(Book(title="book_%s" % i,price = random.randint(30,200)))
#Book.objects.bulk_create(temp_list)
book_list = Book.objects.all()
#分页器的基本语法
# 实例化分页器对象
paginator = Paginator(book_list, 10)
#print("count", paginator.count) # 数据的总数
#print("num_pages", paginator.num_pages) # 分页的总页数
#print("page_range", paginator.page_range) # 页数的范围列表
page1 = paginator.get_page(1)
page2 = paginator.get_page(2)
#for i in page1:
# print(i)
print(page1.object_list)
#把book_list传到模板层
return render(request,"book_list.html",{
"book_list":book_list,
})
访问http://127.0.0.1:8000/app01/book_list/,调试输出,是query_set对象
<QuerySet [<Book: Book object (101)>, <Book: Book object (102)>, <Book: Book object (103)>, <Book: Book object (104)>, <Book: Book object (105)>, <Book: Book object (106)>, <Book: Book object (107)>, <Book: Book object (108)>, <Book: Book object (109)>, <Book: Book object (110)>]>
查看是否有上一页或者下一页
#分页器
from app01.models import Book
#from app01 import models
import random
from django.core.paginator import Paginator
class Booklist(View):
def get(self,request):
#temp_list = []
#for i in range(1,101):
#Book.objects.create(title="book_%s" % i,price = random.randint(30,200))
# temp_list.append(Book(title="book_%s" % i,price = random.randint(30,200)))
#Book.objects.bulk_create(temp_list)
book_list = Book.objects.all()
#分页器的基本语法
# 实例化分页器对象
paginator = Paginator(book_list, 10)
#print("count", paginator.count) # 数据的总数
#print("num_pages", paginator.num_pages) # 分页的总页数
#print("page_range", paginator.page_range) # 页数的范围列表
#page1 = paginator.get_page(1)
page2 = paginator.get_page(2)
#for i in page1:
# print(i)
#print(page1.object_list)
print(page2.has_next()) # 是否有下一页
print(page2.next_page_number()) # 下一页的页码
print(page2.has_previous()) # 是否有上一页
print(page2.previous_page_number()) # 上一页的页码
#把book_list传到模板层
return render(request,"book_list.html",{
"book_list":book_list,
})
访问http://127.0.0.1:8000/app01/book_list/,调试输出
True
3
True
1
这两个报错
# page=paginator.page(22) # error:EmptyPage
# page=paginator.page("z") # error:PageNotAnInteger
原因:
进入get_page查看源码
def get_page(self, number):
"""
Return a valid page, even if the page argument isn't a number or isn't
in range.
"""
try:
number = self.validate_number(number)
except PageNotAnInteger:
number = 1 #非数字转为1
except EmptyPage:
number = self.num_pages #空转为最大页数
return self.page(number)
使用get就不会报错
views文件
#分页器
from app01.models import Book
#from app01 import models
import random
from django.core.paginator import Paginator
class Booklist(View):
def get(self,request):
book_list = Book.objects.all()
#分页器的基本语法
# 实例化分页器对象
paginator = Paginator(book_list, 10)
#基本使用
#获取当前页
current_page = request.GET.get('page')
#获取当前页数据,同时在html中循环
page = paginator.get_page(current_page) #把book_list传到模板层
return render(request,"book_list.html",{
#"book_list":book_list,
"page": page
})
html文件
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<h3>图书列表</h3>
<ul>
{% for book in page %}
<li>{{ book.title }}---价格---{{ book.price }}</li>
{% endfor %}
</ul>
</body>
</html>
访问http://127.0.0.1:8000/app01/book_list/,为空,显示第一页
访问http://127.0.0.1:8000/app01/book_list/?page=4,显示第四页
3 添加分页器
使用bootstrap做分页器显示
静态文件配置
root@darren-virtual-machine:~/PycharmProjects/cbv_test# mkdir statics
root@darren-virtual-machine:~/PycharmProjects/cbv_test# mkdir statics/css statics/js statics/images statics/plugins
root@darren-virtual-machine:~/PycharmProjects/cbv_test# ll statics/plugins/
drwxr-xr-x 5 root root 4096 4月 11 08:38 bootstrap-3.4.1-dist/
注册静态文件
STATIC_URL = '/static/'
STATICFILES_DIRS = [
os.path.join(BASE_DIR,"statics"),
]
html添加样式
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<link rel="stylesheet" href="/static/plugins/bootstrap-3.4.1-dist/css/bootstrap.css">
</head>
<body>
<h3>图书列表</h3>
<ul>
{% for book in page %}
<li>{{ book.title }}---价格---{{ book.price }}</li>
{% endfor %}
</ul>
<nav aria-label="Page navigation">
<ul class="pagination">
<li>
<a href="#" aria-label="Previous">
<span aria-hidden="true">«</span>
</a>
</li>
<li><a href="#">1</a></li>
<li><a href="#">2</a></li>
<li><a href="#">3</a></li>
<li><a href="#">4</a></li>
<li><a href="#">5</a></li>
<li>
<a href="#" aria-label="Next">
<span aria-hidden="true">»</span>
</a>
</li>
</ul>
</nav>
</body>
</html>
访问http://127.0.0.1:8000/app01/book_list/如下
下面应该可以显示所有的页面,使用一个for循环
views,把页数传递到html
#分页器
from app01.models import Book
#from app01 import models
import random
from django.core.paginator import Paginator
class Booklist(View):
def get(self,request):
book_list = Book.objects.all()
#分页器的基本语法
# 实例化分页器对象
paginator = Paginator(book_list, 10)
#基本使用
#获取当前页
current_page = request.GET.get('page')
#获取当前页数据,同时在html中循环
page = paginator.get_page(current_page) #把book_list传到模板层
return render(request,"book_list.html",{
#"book_list":book_list,
"page": page,
"paginator" :paginator
})
html文件
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<link rel="stylesheet" href="/static/plugins/bootstrap-3.4.1-dist/css/bootstrap.css">
</head>
<body>
<h3>图书列表</h3>
<ul>
{% for book in page %}
<li>{{ book.title }}---价格---{{ book.price }}</li>
{% endfor %}
</ul>
<nav aria-label="Page navigation">
<ul class="pagination">
<li>
<a href="#" aria-label="Previous">
<span aria-hidden="true">«</span>
</a>
</li>
{% for num in paginator.page_range %}
<li><a href="?page={{ num }}">{{ num }}</a></li>
{% endfor %}
<li>
<a href="#" aria-label="Next">
<span aria-hidden="true">»</span>
</a>
</li>
</ul>
</nav>
</body>
</html>
访问显示
4 分页器添加上一页和下一页代码
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<link rel="stylesheet" href="/static/plugins/bootstrap-3.4.1-dist/css/bootstrap.css">
</head>
<body>
<h3>图书列表</h3>
<ul>
{% for book in page %}
<li>{{ book.title }}---价格---{{ book.price }}</li>
{% endfor %}
</ul>
<nav aria-label="Page navigation">
<ul class="pagination">
{% if page.has_previous %}
<li>
<a href="?page={{ page.previous_page_number }}" aria-label="Previous">
<span aria-hidden="true">«</span>
</a>
</li>
{% else %}
<li class="disabled">
<a href="javascript:void(0)" aria-label="Previous">
<span aria-hidden="true">«</span>
</a> {% endif %} {% for num in paginator.page_range %}
<li><a href="?page={{ num }}">{{ num }}</a></li>
{% endfor %}
{% if page.has_next %}
<li>
<a href="?page={{ page.next_page_number }}" aria-label="Next">
<span aria-hidden="true">»</span>
</a>
</li>
{% else %}
<li class="disabled">
<a href="javascript:void(0)" aria-label="Next">
<span aria-hidden="true">»</span>
</a>
</li> {% endif %} </ul>
</nav>
</body>
</html>
访问效果
5 分页器添加首页和尾页
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<link rel="stylesheet" href="/static/plugins/bootstrap-3.4.1-dist/css/bootstrap.css">
</head>
<body>
<h3>图书列表</h3>
<ul>
{% for book in page %}
<li>{{ book.title }}---价格---{{ book.price }}</li>
{% endfor %}
</ul>
<nav aria-label="Page navigation">
<ul class="pagination">
<li><a href="?page=1">首页</a></li>
{% if page.has_previous %}
<li>
<a href="?page={{ page.previous_page_number }}" aria-label="Previous">
<span aria-hidden="true">«</span>
</a>
</li>
{% else %}
<li class="disabled">
<a href="javascript:void(0)" aria-label="Previous">
<span aria-hidden="true">«</span>
</a> {% endif %} {% for num in paginator.page_range %}
<li><a href="?page={{ num }}">{{ num }}</a></li>
{% endfor %}
{% if page.has_next %}
<li>
<a href="?page={{ page.next_page_number }}" aria-label="Next">
<span aria-hidden="true">»</span>
</a>
</li>
{% else %}
<li class="disabled">
<a href="javascript:void(0)" aria-label="Next">
<span aria-hidden="true">»</span>
</a>
</li> {% endif %}
<li><a href="?page={{ paginator.num_pages }}">尾页</a></li>
</ul>
</nav>
</body>
</html>
访问效果
6 分页器添加当前页标记
views文件传递参数
#分页器
from app01.models import Book
#from app01 import models
import random
from django.core.paginator import Paginator
class Booklist(View):
def get(self,request):
book_list = Book.objects.all()
#分页器的基本语法
# 实例化分页器对象
paginator = Paginator(book_list, 10)
#基本使用
#获取当前页,在后面需要进行对当前页标记,和num比较,需要转换成int类型
current_page = int(request.GET.get('page',1))
#获取当前页数据,同时在html中循环
page = paginator.get_page(current_page) #把book_list传到模板层
return render(request,"book_list.html",{
#"book_list":book_list,
"page": page,
"paginator" :paginator,
"current_page": current_page
})
html文件配置
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<link rel="stylesheet" href="/static/plugins/bootstrap-3.4.1-dist/css/bootstrap.css">
</head>
<body>
<h3>图书列表</h3>
<ul>
{% for book in page %}
<li>{{ book.title }}---价格---{{ book.price }}</li>
{% endfor %}
</ul>
<nav aria-label="Page navigation">
<ul class="pagination">
<li><a href="?page=1">首页</a></li>
{% if page.has_previous %}
<li>
<a href="?page={{ page.previous_page_number }}" aria-label="Previous">
<span aria-hidden="true">«</span>
</a>
</li>
{% else %}
<li class="disabled">
<a href="javascript:void(0)" aria-label="Previous">
<span aria-hidden="true">«</span>
</a> {% endif %} {% for num in paginator.page_range %}
{% if num == current_page %}
<li class="active"><a href="?page={{ num }}">{{ num }}</a></li>
{% else %}
<li><a href="?page={{ num }}">{{ num }}</a></li>
{% endif %}
{% endfor %}
{% if page.has_next %}
<li>
<a href="?page={{ page.next_page_number }}" aria-label="Next">
<span aria-hidden="true">»</span>
</a>
</li>
{% else %}
<li class="disabled">
<a href="javascript:void(0)" aria-label="Next">
<span aria-hidden="true">»</span>
</a>
</li> {% endif %}
<li><a href="?page={{ paginator.num_pages }}">尾页</a></li>
</ul>
</nav>
</body>
</html>
当有50页显示时,例如将每页显示2
paginator = Paginator(book_list, 2)
显示如下
7 显示改进
views文件
from django.shortcuts import render,redirect,HttpResponse
from django.views import View
import time
from django.utils.decorators import method_decorator # Create your views here. def timer(func):
def inner(request,*args,**kwargs):
start_time = time.time()
time.sleep(2)
rep = func(request,*args,**kwargs)
end_time = time.time()
print (end_time-start_time)
return rep
return inner #FBV
@timer
def login(request):
if request.method == "GET":
return render(request,"login.html")
else:
username = request.POST.get("username")
password = request.POST.get("password")
if username == "joy" and password == "123456":
return HttpResponse("login success...")
else:
return render(request,"login.html") #CBV
@method_decorator(timer,name="get")
class Login(View):
#@method_decorator(timer)
def dispatch(self, request, *args, **kwargs):
obj = super().dispatch(request,*args,**kwargs)
return obj #这里必须返回,否则Httpresponse错误
#@method_decorator(timer)
def get(self,request):
return render(request, "login.html")
def post(self,request):
username = request.POST.get("username")
password = request.POST.get("password")
if username == "joy" and password == "123456":
return HttpResponse("login success...")
else:
return render(request, "login.html") #分页器
from app01.models import Book
#from app01 import models
import random
from django.core.paginator import Paginator
class Booklist(View):
def get(self,request):
book_list = Book.objects.all()
#分页器的基本语法
# 实例化分页器对象
paginator = Paginator(book_list, 2)
#基本使用
#获取当前页,在后面需要进行对当前页标记,和num比较,需要转换成int类型
current_page = int(request.GET.get('page',1))
#获取当前页数据,同时在html中循环
page = paginator.get_page(current_page)
# 我们按照页面显示11个页码为例。
# 如果总页码大于11
if paginator.num_pages > 11:
if current_page - 5 < 1: # 当前页小于中间页码时
page_range = range(1, 12)
elif current_page + 5 > paginator.num_pages: # 当前页大于中间页码时
page_range = range(paginator.num_pages - 10, paginator.num_pages + 1)
else:
page_range = range(current_page - 5, current_page + 6)
else:
page_range = paginator.page_range
#把book_list传到模板层
return render(request,"book_list.html",{
#"book_list":book_list,
"page": page,
"paginator" :paginator,
"current_page": current_page,
"page_range": page_range
})
html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<link rel="stylesheet" href="/static/plugins/bootstrap-3.4.1-dist/css/bootstrap.css">
</head>
<body>
<h3>图书列表</h3>
<ul>
{% for book in page %}
<li>{{ book.title }}---价格---{{ book.price }}</li>
{% endfor %}
</ul>
<nav aria-label="Page navigation">
<ul class="pagination">
<li><a href="?page=1">首页</a></li>
{% if page.has_previous %}
<li>
<a href="?page={{ page.previous_page_number }}" aria-label="Previous">
<span aria-hidden="true">«</span>
</a>
</li>
{% else %}
<li class="disabled">
<a href="javascript:void(0)" aria-label="Previous">
<span aria-hidden="true">«</span>
</a> {% endif %} {% for num in page_range %}
{% if num == current_page %}
<li class="active"><a href="?page={{ num }}">{{ num }}</a></li>
{% else %}
<li><a href="?page={{ num }}">{{ num }}</a></li>
{% endif %}
{% endfor %}
{% if page.has_next %}
<li>
<a href="?page={{ page.next_page_number }}" aria-label="Next">
<span aria-hidden="true">»</span>
</a>
</li>
{% else %}
<li class="disabled">
<a href="javascript:void(0)" aria-label="Next">
<span aria-hidden="true">»</span>
</a>
</li> {% endif %}
<li><a href="?page={{ paginator.num_pages }}">尾页</a></li>
</ul>
</nav>
</body>
</html>
效果如下,前面
中间
最后
保证每页显示11个
8 自定制分页器
root@darren-virtual-machine:~/PycharmProjects/cbv_test# vim app01/utils.py
class Paginator:
def __init__(self, current_page, all_count, per_page=10, max_page_num=11):
"""
封装分页相关数据
:param current_page: 当前页码
:param all_count: 数据库中的数据总条数
:param per_page: 每个页面显示的数据条数
:param max_page_num: 最多显示的页码个数
:param num_pages: 通过总条数/每个页面显示的条数，求出总页数
"""
try:
current_page = int(current_page)
except Exception as e:
current_page = 1
if current_page < 1:
current_page = 1
self.current_page = current_page
self.all_count = all_count
self.per_page = per_page # 计算总页数
num_pages, temp = divmod(all_count, per_page)
if temp:
num_pages += 1
self.num_pages = num_pages self.max_page_num = max_page_num # 11
self.page_count_half = int((self.max_page_num - 1) / 2) # 5
"""
self.num_pages=100
per_page=8 current_page =1 [0:8]
current_page =2 [8:16]
current_page =3 [16:24]
[(current_page-1)*per_page:current_page*per_page ] """ @property
def start(self):
return (self.current_page - 1) * self.per_page @property
def end(self):
return self.current_page * self.per_page def page_html(self):
# 如果总页数小于self.max_page_num(最多显示的页码个数)
if self.num_pages <= self.max_page_num:
page_start = 1
page_end = self.num_pages + 1
else:
# 如果当前页码<=页面上最多显示11/2个页码时
if self.current_page <= self.page_count_half:
page_start = 1
page_end = self.max_page_num + 1
# 如果当前页码+最多显示11/2 大于 总页数时
elif self.current_page + self.page_count_half > self.num_pages:
page_start = self.num_pages - self.max_page_num + 1
page_end = self.num_pages + 1
else:
page_start = self.current_page - self.page_count_half
page_end = self.current_page + self.page_count_half + 1 page_html_list = [] # 首页
first_page = '<nav aria-label="Page navigation"><ul class="pagination"><li><a href="?page=1">首页</a></li>'
page_html_list.append(first_page) # 上一页
if self.current_page <= 1:
prev_page = '<li class="disabled"><a href="javascript:void(0);">上一页</a></li>'
else:
prev_page = '<li><a href="?page=%s">上一页</a></li>' % (self.current_page - 1, )
page_html_list.append(prev_page) # 显示页码
for i in range(page_start, page_end):
if self.current_page == i:
temp = '<li class="active"><a href="?page=%s">%s</a></li>' % (i, i)
else:
temp = '<li><a href="?page=%s">%s</a></li>' % (i, i)
page_html_list.append(temp) # 下一页
if self.current_page >= self.num_pages:
next_page = '<li class="disabled"><a href="javascript:void(0);">下一页</a></li>'
else:
next_page = '<li><a href="?page=%s">下一页</a></li>' % (self.current_page + 1)
page_html_list.append(next_page) # 尾页
last_page = '<li><a href="?page=%s">尾页</a></li></ul></nav>' % self.num_pages
page_html_list.append(last_page) return "".join(page_html_list)
视图调用
#分页器
from app01.models import Book
#from app01 import models
import random
from django.core.paginator import Paginator
#为了避免重复,取得别名
from app01.utils import Paginator as MyPaginator
class Booklist(View):
def get(self,request):
book_list = Book.objects.all()
#分页器的基本语法
# 实例化分页器对象
#paginator = Paginator(book_list, 2)
#基本使用
#获取当前页,在后面需要进行对当前页标记,和num比较,需要转换成int类型
current_page = int(request.GET.get('page',1))
#获取当前页数据,同时在html中循环
#page = paginator.get_page(current_page)
# 我们按照页面显示11个页码为例。
# 如果总页码大于11
#if paginator.num_pages > 11:
# if current_page - 5 < 1: # 当前页小于中间页码时
# page_range = range(1, 12)
# elif current_page + 5 > paginator.num_pages: # 当前页大于中间页码时
# page_range = range(paginator.num_pages - 10, paginator.num_pages + 1)
# else:
# page_range = range(current_page - 5, current_page + 6)
#else:
# page_range = paginator.page_range
paginator = MyPaginator(current_page, book_list.count(), 8, 11)
book_list = book_list[paginator.start:paginator.end]
#把book_list传到模板层
#return render(request,"book_list.html",{
return render(request, "book_list1.html", {
"book_list":book_list,
#"page": page,
"paginator" :paginator,
"current_page": current_page,
#"page_range": page_range,
#"book_list":book_list,
})
book_list1.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<link rel="stylesheet" href="/static/plugins/bootstrap-3.4.1-dist/css/bootstrap.css">
</head>
<body>
<h3>书籍列表!!!</h3> <ul>
{% for book in book_list %}
<li>{{ book.title }}---价格---{{ book.price }}</li>
{% endfor %}
</ul>
{{ paginator.page_html|safe }}
</body>
</html>
结果
9 带参数分页器调用
如果需要携带参数
utils文件
class Paginator:
def __init__(self, request, current_page, all_count, per_page=10, max_page_num=11):
"""
封装分页相关数据
:param current_page: 当前页码
:param all_count: 数据库中的数据总条数
:param per_page: 每个页面显示的数据条数
:param max_page_num: 最多显示的页码个数
:param num_pages: 通过总条数/每个页面显示的条数，求出总页数
"""
try:
current_page = int(current_page)
except Exception as e:
current_page = 1
if current_page < 1:
current_page = 1
self.current_page = current_page
self.all_count = all_count
self.per_page = per_page # 计算总页数
num_pages, temp = divmod(all_count, per_page)
if temp:
num_pages += 1
self.num_pages = num_pages self.max_page_num = max_page_num # 11
self.page_count_half = int((self.max_page_num - 1) / 2) # 5 import copy
self.url_args = copy.deepcopy(request.GET)
print(self.url_args.urlencode())
"""
self.num_pages=100
per_page=8 current_page =1 [0:8]
current_page =2 [8:16]
current_page =3 [16:24]
[(current_page-1)*per_page:current_page*per_page ] """ @property
def start(self):
return (self.current_page - 1) * self.per_page @property
def end(self):
return self.current_page * self.per_page def page_html(self):
# 如果总页数小于self.max_page_num(最多显示的页码个数)
if self.num_pages <= self.max_page_num:
page_start = 1
page_end = self.num_pages + 1
else:
# 如果当前页码<=页面上最多显示11/2个页码时
if self.current_page <= self.page_count_half:
page_start = 1
page_end = self.max_page_num + 1
# 如果当前页码+最多显示11/2 大于 总页数时
elif self.current_page + self.page_count_half > self.num_pages:
page_start = self.num_pages - self.max_page_num + 1
page_end = self.num_pages + 1
else:
page_start = self.current_page - self.page_count_half
page_end = self.current_page + self.page_count_half + 1 page_html_list = [] # 首页
self.url_args['page'] = 1
#first_page = '<nav aria-label="Page navigation"><ul class="pagination"><li><a href="?page=1">首页</a></li>'
first_page = '<nav aria-label="Page navigation"><ul class="pagination"><li><a href="?page=%s">首页</a></li>' % self.url_args.urlencode()
page_html_list.append(first_page) # 上一页
if self.current_page <= 1:
prev_page = '<li class="disabled"><a href="javascript:void(0);">上一页</a></li>'
else:
self.url_args['page'] = self.current_page - 1
#prev_page = '<li><a href="?page=%s">上一页</a></li>' % (self.current_page - 1, )
prev_page = '<li><a href="?%s">上一页</a></li>' % self.url_args.urlencode()
page_html_list.append(prev_page) # 显示页码
for i in range(page_start, page_end):
self.url_args['page'] = i
if self.current_page == i:
#temp = '<li class="active"><a href="?page=%s">%s</a></li>' % (i, i)
temp = '<li class="active"><a href="?%s">%s</a></li>' % (self.url_args.urlencode(), i)
else:
#temp = '<li><a href="?page=%s">%s</a></li>' % (i, i)
temp = '<li><a href="?%s">%s</a></li>' % (self.url_args.urlencode(), i)
page_html_list.append(temp) # 下一页
if self.current_page >= self.num_pages:
next_page = '<li class="disabled"><a href="javascript:void(0);">下一页</a></li>'
else:
self.url_args['page'] = self.current_page + 1
#next_page = '<li><a href="?page=%s">下一页</a></li>' % (self.current_page + 1)
next_page = '<li><a href="?%s">下一页</a></li>' % self.url_args.urlencode()
page_html_list.append(next_page) # 尾页
self.url_args['page'] = self.num_pages
#last_page = '<li><a href="?page=%s">尾页</a></li></ul></nav>' % self.num_pages
last_page = '<li><a href="?%s">尾页</a></li></ul></nav>' % self.url_args.urlencode()
page_html_list.append(last_page) return "".join(page_html_list)
视图文件
from django.shortcuts import render,redirect,HttpResponse
from django.views import View
import time
from django.utils.decorators import method_decorator # Create your views here. def timer(func):
def inner(request,*args,**kwargs):
start_time = time.time()
time.sleep(2)
rep = func(request,*args,**kwargs)
end_time = time.time()
print (end_time-start_time)
return rep
return inner #FBV
@timer
def login(request):
if request.method == "GET":
return render(request,"login.html")
else:
username = request.POST.get("username")
password = request.POST.get("password")
if username == "joy" and password == "123456":
return HttpResponse("login success...")
else:
return render(request,"login.html") #CBV
@method_decorator(timer,name="get")
class Login(View):
#@method_decorator(timer)
def dispatch(self, request, *args, **kwargs):
obj = super().dispatch(request,*args,**kwargs)
return obj #这里必须返回,否则Httpresponse错误
#@method_decorator(timer)
def get(self,request):
return render(request, "login.html")
def post(self,request):
username = request.POST.get("username")
password = request.POST.get("password")
if username == "joy" and password == "123456":
return HttpResponse("login success...")
else:
return render(request, "login.html") #分页器
from app01.models import Book
#from app01 import models
import random
from django.core.paginator import Paginator
#为了避免重复,取得别名
from app01.utils import Paginator as MyPaginator
class Booklist(View):
def get(self,request):
book_list = Book.objects.all()
#分页器的基本语法
# 实例化分页器对象
#paginator = Paginator(book_list, 2)
#基本使用
#获取当前页,在后面需要进行对当前页标记,和num比较,需要转换成int类型
current_page = int(request.GET.get('page',1))
#获取当前页数据,同时在html中循环
#page = paginator.get_page(current_page)
# 我们按照页面显示11个页码为例。
# 如果总页码大于11
#if paginator.num_pages > 11:
# if current_page - 5 < 1: # 当前页小于中间页码时
# page_range = range(1, 12)
# elif current_page + 5 > paginator.num_pages: # 当前页大于中间页码时
# page_range = range(paginator.num_pages - 10, paginator.num_pages + 1)
# else:
# page_range = range(current_page - 5, current_page + 6)
#else:
# page_range = paginator.page_range
paginator = MyPaginator(request,current_page, book_list.count(), 8, 11)
book_list = book_list[paginator.start:paginator.end]
#把book_list传到模板层
#return render(request,"book_list.html",{
return render(request, "book_list1.html", {
"book_list":book_list,
#"page": page,
"paginator" :paginator,
"current_page": current_page,
#"page_range": page_range,
#"book_list":book_list,
})
访问http://127.0.0.1:8000/app01/book_list/?page=10&name=joy&password=123结果如下
当代有参数时,把鼠标放在不分页器上,最下面可以显示到后面页带的有参数
参考文档:https://www.cnblogs.com/Michael--chen/p/10965465.html
老男孩教育视频:https://www.oldboyedu.com/
063.Python前端Django分页器的更多相关文章
- 058.Python前端Django与Ajax
一 Ajax简介 AJAX(Asynchronous Javascript And XML)翻译成中文就是"异步Javascript和XML".即使用Javascript语言与服务 ...
- 055.Python前端Django模型ORM
由于前面在centos实验的过程中,pymql一直有属性错误,很难排查出问题,重新做了一个ubuntu的桌面系统同时使用pycharm开发工具作为学习开发工具,具体原因是因为在项目命名出现问题,和自己 ...
- 052.Python前端Django框架路由层和视图层
一.路由层(URLconf) 1.1 路由层简单配置 URL配置(URLconf)就像Django 所支撑网站的目录.它的本质是URL与要为该URL调用的视图函数之间的映射表:你就是以这种方式告诉Dj ...
- 061.Python前端Django组件用户认证组件
一 auth认证组件 在使用pymysql,数据库迁移的时候.,默认生成有十张表如下 查看author_user表结构 mysql> desc auth_user; +------------- ...
- 059.Python前端Django组件cooki和session
一 会话跟踪技术 1.1 什么是会话 会话是指一个终端用户(服务器)与交互系统(客户端)进行通讯的过程. 1.2 什么是会话跟踪 对同一个用户对服务器的连续的请求和接受响应的监视.(将用户与同一用户发 ...
- 057.Python前端Django模型ORM多表查询
一 基于对象的查询 1.1 一对多查询 设计路由 from django.contrib import admin from django.urls import path from app01 im ...
- 056.Python前端Django模型ORM多表基本操作
一 准备工作 1.1 新建一个项目 root@darren-virtual-machine:~# cd /root/PycharmProjects/ root@darren-virtual-machi ...
- 053.Python前端Django框架模板层
模板层 一 模板语法之变量 在 Django 模板中遍历复杂数据结构的关键是句点字符, 语法: {{ var_name }} [root@node10 mysite]# cat app01/urls. ...
- [Python] 利用Django进行Web开发系列（一）
1 写在前面 在没有接触互联网这个行业的时候,我就一直很好奇网站是怎么构建的.现在虽然从事互联网相关的工作,但是也一直没有接触过Web开发之类的东西,但是兴趣终归还是要有的,而且是需要自己动手去实践的 ...
随机推荐
- 一文彻底掌握Apache Hudi的主键和分区配置
1. 介绍 Hudi中的每个记录都由HoodieKey唯一标识,HoodieKey由记录键和记录所属的分区路径组成.基于此设计Hudi可以将更新和删除快速应用于指定记录.Hudi使用分区路径字段对数据 ...
- （十二）struts2的类型转换
所有的MVC框架,都属于表现层的解决方案,都需要负责收集用户请求参数,并将请求参数传给应用的控制器组件. 这时问题出现了,所有的请求参数都是字符串类型数据,因此MVC框架必须具备将这些字符串请求参数转 ...
- JVM--Java核心面试知识整理（一）
JVM 基本概念 JVM 是可运行 Java 代码的假想计算机 ,包括一套字节码指令集.一组寄存器.一个栈. 一个垃圾回收,堆和 一个存储方法域.JVM 是运行在操作系统之上的,它与硬件没有直接的交互 ...
- manjaro找不到默认键盘布局
1 问题描述 manjaro安装fcitx后,没有默认的键盘布局,不是这样: 而是: 2 解决方案 解决方案在启动fcitx时就已经有提示了: 缺少了libjson-c这个库,直接使用pacman搜索 ...
- Web操作摄像头、高拍仪、指纹仪等设备的功能扩展方案
摘要:信息系统开发中难免会有要操作摄像头.高拍仪.指纹仪等硬件外设,异或诸如获取机器签名.硬件授权保护(加密锁)检测等情况.受限于Web本身运行机制,就不得不使用Active.浏览器插件进行能力扩展了 ...
- Mysql下可能存在注入的点。
总结下mysql下可能存在注入的点,适用于mssql和oracle,先写语句,以后再写语句可能出现在哪些场景下: 针对查询: select * from x where id=* select * f ...
- python 爬取王者荣耀英雄皮肤代码
import os, time, requests, json, re, sys from retrying import retry from urllib import parse "& ...
- misdirection靶机work_through
web打点 nmap扫描 Nmap scan report for 192.168.218.135 Host is up (0.000014s latency). Not shown: 65531 c ...
- 【js】Leetcode每日一题-叶子相似的树
[js]Leetcode每日一题-叶子相似的树 [题目描述] 请考虑一棵二叉树上所有的叶子,这些叶子的值按从左到右的顺序排列形成一个 叶值序列 . 举个例子,如上图所示,给定一棵叶值序列为 (6, 7 ...
- 一、unittest介绍与基础使用
一.unittest为单元测试框架,系统标准库 import unittest